Even in the off-season there are 450 immaculately turned out members of staff at the Royal Mansour on Morocco’s Mediterranean coast. They pander to the needs of the guests housed in just 55 suites and villas and wear, by my reckoning, 17 distinct styles of uniform.

The butlers have crisp beige suits, the waiters green silk blouses, and the man who drives the luggage cart dazzles in a bright red uniform with matching cap. There are special outfits, mostly in understated colours, for the concierge staff, the engineers, the various ranks of housekeepers, as well as for those who deliver room service.

The mystery is: where are they all hiding? You can stroll along the beautiful sandy beach picking up vibrant-coloured shells, or cycle along the swept paths through the hotel’s lovely manicured gardens, and think yourself virtually alone. A few greeters and gardeners (in their own rustic outfits) are dotted about, but there’s no one shuttling between the lobby and the sand-coloured villas. Even the private butlers appear to be invisible, popping up as if by magic only when their discreet services are required.

It is only later that I solve the riddle of the disappearing staff. Beneath the hotel complex is a secret network of tunnels. Out of sight and out of earshot, members of staff flit along in vehicles beneath the surface, rising in dedicated lifts to deliver champagne and trays of Moroccan sweets, to plump pillows and to arrange the poolside towels just-so. It is not so much upstairs-downstairs as overground-underground.

If it is service fit for a king, that is no coincidence. The hotel is owned by Mohammed VI, Morocco’s monarch since 1999. In 2010 he opened the Royal Mansour in Marrakech — a no-expense-spared celebration of Moroccan craftsmanship, newly built but with swathes of intricate zellij mosaics and traditional hand-sculpted plasterwork. Rather than rooms, its guests stay in their own private riads, arranged in a sort of simulacrum of the medina. Some visitors have found an eeriness in the way the real city’s colour and chaos have been substituted for jasmine-scented silence, but the hotel has been a hit, drawing a string of celebrities and commanding room rates that rarely dip below £1,300 per night.

In April this year a second Royal Mansour opened, a marble-lined tower in the country’s economic and financial hub, Casablanca. And now the royal hotel group has launched its first beach hotel, here at Tamuda Bay. The king is unlikely actually to stay — he has a rather nice beachside pad-cum-palace right next door — but friends and members of his extended family were apparently frequent visitors in the run-up to the official opening last month.

If the movements of the staff are a well-kept secret so, in its way, is Morocco’s Mediterranean coast, at least outside the kingdom. With the Rif mountains arcing in the background, it extends for almost 400km, from the Spanish enclave of Ceuta all the way to the Algerian border in the east.

Though the Atlantic coast, and towns such as Essaouira, Agadir, Oualidia and Taghazout, are better known internationally, the stretch of Mediterranean coastline around the Royal Mansour and the little town of M’diq turns out to be where the country’s jet-set spend their summers, eating the local sardines in beachside restaurants and feeding the wild boars which come down from the wooded hillsides.

By October, when I visit, the king and his retinue have moved on, the boars are gone and the hullabaloo has quelled. Yet the temperature is still a glorious 27 degrees and the sky and ocean — at least during my stay — are improbable shades of uninterrupted blue. Only a three-hour flight from London, plus a 90-minute drive from Tangier airport in the hotel’s electric car, it makes for a viable winter getaway (especially given rates remain far below those of the Marrakech property).

I arrive at night and am golf-carted to my room. The hotel’s complex stretches a good half-mile along a wide private beach of fine sand. In the morning, the ocean is a leisurely 60-second walk away, assuming one is not waylaid by the swimming pool.

A series of low-rise buildings each house between four and eight suites; the seven villas are spread out for seclusion with their beach area further hidden by sand dunes. If walking to the main lobby seems too far, guests can go by golf-cart (courtesy of the man in red) or cycle. Wherever you abandon your bike, it mysteriously winds up next to your suite again, as if delivered by invisible pixies.

Though the decor is opulent, the tile work and woven carpets are in muted, rather soothing, colours. In the day, the light against the crisp lines of the hotel buildings’ walls has a stark, David Hockney quality. As the sun sets, the blues and beiges blur into the ocean, the sand and the purplish night air.

The hotel has multiple restaurants (including one Spanish, one French and one Italian) and a huge spa on two floors offering both therapeutic and hedonistic treatments. Children are welcome. Those aged four to 12 can be deposited in a kids club, almost as tastefully decorated as the adult quarters, where they are entertained, according to the hotel bumf, with calligraphy, music and cooking lessons — and no doubt with video games and cartoons when their parents’ backs are turned.

One day, I take a tour to the nearby walled city of Tétouan, a 25-minute drive away and about 40km south of the Strait of Gibraltar. Home to about 380,000 and a medina that is a Unesco World Heritage Site, it is an unexpected gem. In the second century BC, the region’s first inhabitants traded with Phoenicians and were later colonised by Romans and Berbers, but the city’s modern history began in the 15th century when it was settled by Muslims and Jews from Andalusia. When the last Moriscos were expelled from Spain between 1609 and 1614, many came to Tétouan, which is sometimes known as “Granada’s daughter”. In 1913, it became the capital of the Spanish Protectorate of northern Morocco, which lasted a little over 40 years.

Today it is a pleasant place to walk around, a curious mix of art deco in eye-dazzling white, heavy Andalusian doors and Moroccan riads, with their courtyard gardens. Spanish cafés selling bocadillos and strong black coffee sit side by side with outlets offering sweet cakes and syrupy mint tea. The maze-like medina, with its Jewish and Muslim quarters, is a mini-Marrakech, arguably more interesting because less touristic.

Morocco is starting to market the Mediterranean coast abroad and several grand hotels have opened on this stretch of coastline, including the St Regis and the Ritz-Carlton. But if your idea of luxury is an invisible retinue of underground staff and a monarch as an occasional next door neighbour, then there is probably only one choice.

David Pilling is the FT’s Africa editor

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